At present, several rows of orientable vanes may outfit a stator housing of a compressor of a turbojet engine. Such vanes can pivot during the operation of the engine. Their cambered blades tilt in relation to the primary flow passing through them, making it possible to adapt their action depending on the engine conditions and the flight conditions. The operating range is thus extended, and the efficiency is optimized.
The performance of the compressor is based on the precision of angular positioning of the vanes with respect to the housing, as well as the positioning of the vanes relative to each other. The precision of relative positioning of the vanes is understood both within their row but also in regard to the other rows. In particular, the efficiency requires the vanes to form a blading which best conforms to a predefined geometry.
Document US 2014/0182292 A1 discloses a dual-flow turbofan. The turbofan comprises a low-pressure compressor provided with several rows of vanes, one row of vanes of the stator having a variable geometry. The different rows of vanes of the stator are supported by dedicated external shrouds; these various external shrouds are fixed one after the other by means of radial annular flanges. This configuration enables a mounting when a monobloc bladed disk is present. In fact, the compressor is assembled by alternately securing the rows of rotor vanes and the rows of stator vanes. Each of these rows forms a ring which is brought axially against its support and which radially overlaps the row of vanes downstream from it. Now, this architecture is particularly bulky. Furthermore, the efficiency of such a turbine engine is limited.